• Journal of Preventive Medicine and Public Health
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• 제7권2호
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• pp.373-375
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• 1974

일산화(一酸化) 탄소(炭素)에 대한 피해와 대기오염(大氣汚染) 기준을 아황산(亞黃酸)까스를 기준으로 한다는 데의 관심을 가지고 가정에서 많이 사용하고 인는 연탄을 중심으로 관찰한 결과 CO는 연소온도와 비례하나 $SO_2$는 비례하지 않으며 일단 발생된 CO는 적어도 24시간(時間) 이내에는 변화가 거의 없으며 비교적 장시간 유지한다. $SO_2$는 대기중에서 곧 변화를 일으켜 ($H_{2}SO_{4}$로 전환) 30분이내에 극소량으로 되므로 대기중의 황화물 측정은 $SO_2$보다 유황자체나 $H_{2}SO_{4}$를 측정함이 더욱 효과적이라 하겠다.

• 한국연소학회지
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• 제13권3호
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• pp.9-16
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• 2008

In this study, a cylindrical constant volume combustion chamber is used to investigate the flow and combustion characteristics of methane-air homogeneous mixture under various initial charge pressure, excess air ratios and ignition times. The flame and burning speed, mean gas speed are calculated by numerical analysis to analyze the combustion characteristics. It is found that the mean gas velocity during combustion has the maximum value around 300 ms and then decreased gradually on the condition of 10000 ms, and that the combustion duration is shorten and flame speed and burning velocity have the highest value under the conditions of an excess air ratio 1.1, an initial charge pressure of 0.2 MPa and an ignition time of 300 ms in the present study. And, the initial pressure and burning speed are in inverse proportion, so that it is in agreement with Strehlow who presented that the initial pressure and burning speed are in inverse proportion when the burning speed is under 50cm/s.

• 한국화재소방학회논문지
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• 제10권1호
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• pp.44-48
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• 1996

Burning rate of immobilized methyl and ethyl alcohols on ceramic balls was studied. Experiments were performed by burning methyl, ethyl alcohols immobilized on sands (particle size 0.35mm) and ceramic balls (particle size 1-5mm) to measure mass burning rate, height burning rate and combustion temperature. The longer time from ignition to extinguishment was resulted from the larger particle size of ceramic balls and the smaller size of ceramic balls exhibited the higher mass burning rate. Of alcohols tested the relative magnitude of facilitation of combustion was methyl ＞ ethyl. Combustion temperature of alcohols, without regard to the types of alcohols, was not increased with smaller ceramic balls(up to 3mm of particle size). However, with larger ceramic balls, combustion temperatare of alcohols was increased by 40-50$^{\circ}$ and the highest combustion temperatare was obtained with sands (particle size 0.35mm).

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 춘계학술대회 논문집
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• pp.169-172
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• 2009

본 연구에서는 고연소속도 고체추진제 개발을 위한 현재의 기술들과 연구동향을 분석하였고, 연소속도 조절제에 대한 추진제 적용 및 연소 특성에 대해 검토하였다. 또한 연소속도 조절제로bis(ethylenediamine)copper perchlorate(BECP)를 제조하였고 이의 연소특성이 Butacene/AP 추진제에서 평가되었다. 결과적으로, Butacene과 AP로 구성된 고연소속도 고체 추진제에서 금속배위화합물인 BECP는 고체추진제의 연소속도를 크게 증진시켰다.

• 대한기계학회논문집B
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• 제20권1호
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• pp.244-254
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• 1996

Flow velocity was measured by, use of hot wire anemometer. Turbulence intensity was in proportion to mean flow velocity regardless of swirl velocity. And integral length scale has proportional relation with swirl velocity regardless of measurement position. Turbulent burning speed during flame propagation which was determined by flame photograph and gas pressure of combustion chamber was increased with the lapse of time from spark and was decreased a little at later combustion period. Because of combustion promotion effect, turbulent burning speed was increased according to increase of turbulence intensity. Burning speed ratio i.e. ratio of turbulent burning speed ($S_BT$) to laminar burning speed ($S_BL$) was found out by use of turbulence intensity u' and integral length scale $l_x$ , $\delta_L$ is width of preheat zone in laminar flame.

• 한국대기환경학회지
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• 제32권2호
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• pp.167-175
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• 2016

In this study, we estimate air pollutants emission from agricultural waste burning. We investigated activities related to agricultural waste burning such as crop burning rates, location, and time by region. The average crop burning rates per square meter farmland of fruits, pulses, barleys, cereals, vegetables, and special crops were $273.1g/m^2$, $105.7g/m^2$, $7.4g/m^2$, $121.0g/m^2$, $290.7g/m^2$, and $392.9g/m^2$, respectively. We estimated air pollutants emissions with pre-developed emission factors. The estimated air pollutant emission of agricultural biomass burning were CO 148,028 ton/year, $NO_x$ 5,220 ton/year, $SO_x$ 11 ton/year, VOC 59,767 ton/year, TSP 21,548 ton/year, $PM_{10}$ 8,909 ton/year, $PM_{2.5}$ 7,405 ton/year, and $NH_3$ 5 ton/year. When these results compared with the entire emissions of national inventory (CAPSS), CO, VOC, $PM_{10}$ account for about 17.8%, 6.2%, 6.7% of the total, respectively.

• 한국표면공학회지
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• 제53권1호
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• pp.15-21
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• 2020

In this study, growth and burning behavior of 6061 aluminum alloy was studied under constant anodic voltages at various temperatures and magnetic stirring rates in 20% sulfuric acid solution by analysing I-t curves, measuring thickness and hardness of aluminum anodic oxide (AAO) films, observations of surface and cross-sectional images of AAO films. AAO films were grown continuously at lower voltages than 18.5V but burning occurred when a voltage more than 19V was applied in 20% H₂SO₄ solution at 20±0.5℃ and 200 rpm of magnetic stirring. The burning was always related with an extremely large increase of anodic current density with anodizing time, suggesting that high heat generation during anodizing causes deteriorations of AAO films by chemical reaction with acidic solutions. The burning resulted in decreases of film thickness and hardness, surface color brightened and formation of porous defects in the AAO films. The burning voltage was found to decrease with increasing solution temperature and decreasing magnetic stirring rate. The decreased burning voltages seem to be closely related with increased chemical reactions between AAO films and hydrogen ions.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2002년도 제24회 KOSCO SYMPOSIUM 논문집
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• pp.140-146
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• 2002

The tulip-inversion of flames in half-open tubes was investigated experimentally. Experiments was carried out in tubes with various shapes. The image of a flame propagation were pictured by HICCD(High speed intensified CCD) and the dynamic pressure of tubes was measured by a piezo pressure sensor. By analyzing the images of the flame propagation, we found the time and the distance for the occurrence of tulip-inversion. Regardless of the shapes of tubes, time of tulip-inversion are similar and inversely proportional to the burning velocity. But distances have different tendency. In a straight tube, the distance of tulip-inversion increases when the burning velocity increases. But in a converging tube, the distance of tulip-inversion decreases when a burning velocity increases. And the distance of tulip-inversion in a converging tube is much smaller than the distance of tulip-inversion in a straight tube. These results are caused by the deceleration of a flame when the diameter of a hole in open-side of a tube is small. The deceleration causes little effect on the time of tulip-inversion.

• 한국추진공학회지
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• 제20권1호
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• pp.37-42
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• 2016

본 연구에서는 HTPB를 적용한 고체추진제의 공정간 검사를 위해 경화제를 넣기 전과 넣은 후의 미 경화 추진제의 연소속도를 검토하였다. 그리고 경화제를 넣기 전 미 경화 추진제의 연소속도는 압력 1000 psi에서 약 9.7 mm/s 정도이며, 시간에 따른 연소속도 변화는 없었다. 경화제가 들어간 미 경화 추진제의 연소속도는 약 8.1 mm/s로 시간에 따라 느려지는 경향을 보였다. 경화반응 속도가 느린 미 경화 추진제는 시간에 따라 연소속도가 서서히 느려졌으며, 경화반응 속도가 빠른 미 경화 추진제는 연소속도가 빠르게 느려지는 것을 확인할 수 있었다. 그리고 완전히 경화된 추진제의 연소속도는 약 6.8 mm/s 정도로 가장 느린 것으로 나타났다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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• pp.368-373
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• 2017

본 논문에서는 연소 면적이 시간에 따라 변하는 DACS의 압력 제어 기법을 설계하고 시뮬레이션을 통해 설계된 제어 기법의 성능을 확인하였다. 일반적으로 고체 추진제를 탑재한 DACS는 연소 면적이 일정하도록 설계된다. 이러한 경우 압력 및 추력 제어가 용이하다는 장점은 있으나, 추진제 연소에 의해 생성된 연소 가스가 추력 발생에 사용되지 않고 그대로 배출되는 경우가 발생한다. 따라서 그레인 형상의 최적화 설계가 필요하며, 이러한 경우 연소 면적이 시간에 따라 변하게 된다. 가변하는 연소 면적을 외란으로 가정할 수 있으며 이러한 시스템에 대하여 적응 제어 기법을 적용할 경우 효과적으로 연소관 내부 압력을 제어할 수 있다.